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Just about everyday that I go to start my 66 289 I have a problem keeping it running/idling. Actually starting it is no issue, it fires right up as soon as I turn the key but if I don’t apply a bit of pressure on the gas pedal it sputters out and dies. There are even times where I’ll get it to idle in park for 5 or 6 minutes, throw it into drive or reverse and THEN it decides to sputter out and die. Not exactly sure what the issue is? It recently got a tune in Tulsa, OK and I drove it all the way back here to Los Angeles but along the way had to replace the alternator and battery. Could it just need another tune to be adjusted to residing in LA? Your wisdom is welcome!
 

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Once it’s warmed up, how does it run?
 
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@Knapper Once its warmed up it seems to run just alright, belts squeal a little when accelerating every now and then. But sometimes it still dies out after letting it warm up for close to 10 minutes.
 

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I have the same problem with the hot rod which has no choke and the pick up which has an electric choke. I believe the basic issue is that the engine needs to be thoroughly warmed up before the particles of fuel entering the intake vaporize adequately. Particles of fuel don't burn well so the engine will struggle to idle cleanly. Vaporized fuel is what burns.

In the case of a hot rod with no choke it just is what it is. You not only want the intake warmed up adequately but also the oil and its more critical in something like a hot rod engine. I just idle it for 5 or so minutes until it is warmed up. It also doesn't help in this regard that the engine runs on the cool side so it takes longer to get warm to begin with. If I had an electric water pump that would help it warm up faster by not running it until the engine approached warm running condition. I don't have one though.

In my truck the electric choke warms up faster than the engine and lets off so the engine is still cold. This engine also is cold natured and takes some time to adequately get up to a warm running temperature. I normally idle it until I hear the choke let off then roll it down the highway. it warms up on the street in a minute or 2.

Potentially, a different than stock heat range plug may help. I haven't tried this yet but I plan to.

Adjusting your carb so you have more cold choke if it is not adjusted enough may help compensate because this fattens up the mixture and raises rpms slightly which helps the engine idle better cold.

If you have a low degree opening thermostat moving to a higher one can help warm the engine faster also.

Converting from the electric choke back to a heat riser tube type might also do it because it reacts slower to heat. It will let you run initially with some choke an increased idle rpm to let the engine run easier when cold.

On my hot rod I am considering a small pull cable like a choke cable that puts some higher than idle rpm on the carb for a better cold engine warm up. This would fix me but I don't really want to kludge that up.
 

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1. Are you using the correct procedure to start a cold engine?

a. Depress accelerator pedal slowly to the floor once, to set choke, and release.
b. Turn key to "start".

Engine should start and run at fast idle (about 1,500-1,600 rpm) until choke begins to open, at which point "blipping" the accelerator pedal will knock down the idle when the choke opens to a certain point.

2. Is the choke and choke fast idle linkage working properly?

Following the above procedure (remove air cleaner assembly and observe when performing "step a" you should see the choke plate snap closed and the linkage on the passenger side of the carburetor behind the choke housing should rotate its cam and the fast idle screw should bottom on said cam.
 

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A stone cold engine on the fast idle cam shouldn't actually idle at 1500 or so RPM. That's hard on bearings and automatic transmission engagements. It should idle only 100 or 200 RPM higher than the warm idle. The 1500 - 1600 RPM is what you should get if you rotate the fast idle cam into position when the engine is warmed up. Adjusting the warmed up engine to that speed on the cam stop will result in the few hundred additional RPM when it is cold, as long as you have the rest of the choke system set to give the right mixture.

The service manual lays out all the initial settings for the pulloff, choke cap, and fast idle cam. The pulloff keeps the mixture from being too rich during the first few seconds to minute of cold operation. After that the choke cap and heat source manage the mixture.

If the initial stalling is due to being too rich, you need to make the pulloff open the choke blade a little more. If it is too lean you need to either set the choke cap a little richer or move the pulloff to keep the blade a little more closed.
 

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Really? I didn’t know that it was bad for the bearings to idle cold at 1500 rpm. I don’t have a choke on mine and have to goose the pedal to get it running at first, then hold it a bit around 1200, or 1500. Why would that be bad for the bearings?
 

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A stone cold engine on the fast idle cam shouldn't actually idle at 1500 or so RPM. That's hard on bearings and automatic transmission engagements. It should idle only 100 or 200 RPM higher than the warm idle. The 1500 - 1600 RPM is what you should get if you rotate the fast idle cam into position when the engine is warmed up. Adjusting the warmed up engine to that speed on the cam stop will result in the few hundred additional RPM when it is cold, as long as you have the rest of the choke system set to give the right mixture.

The service manual lays out all the initial settings for the pulloff, choke cap, and fast idle cam. The pulloff keeps the mixture from being too rich during the first few seconds to minute of cold operation. After that the choke cap and heat source manage the mixture.

If the initial stalling is due to being too rich, you need to make the pulloff open the choke blade a little more. If it is too lean you need to either set the choke cap a little richer or move the pulloff to keep the blade a little more closed.
It depends on how long the engine stays on fast idle. The 1966 Ford Factory Service Manual calls for a 1200-1500 rpm setting for fast idle for all carbs/engines. This should only last for about a minute then drop down, you might have to tap the throttle to get it to drop if your choke linkage is a bit sticky. I believe there are 2 slower speed notches on the choke cam before you get to warm idle.
 

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A stone cold engine on the fast idle cam shouldn't actually idle at 1500 or so RPM. That's hard on bearings and automatic transmission engagements. It should idle only 100 or 200 RPM higher than the warm idle. The 1500 - 1600 RPM is what you should get if you rotate the fast idle cam into position when the engine is warmed up. Adjusting the warmed up engine to that speed on the cam stop will result in the few hundred additional RPM when it is cold, as long as you have the rest of the choke system set to give the right mixture.

The service manual lays out all the initial settings for the pulloff, choke cap, and fast idle cam. The pulloff keeps the mixture from being too rich during the first few seconds to minute of cold operation. After that the choke cap and heat source manage the mixture.

If the initial stalling is due to being too rich, you need to make the pulloff open the choke blade a little more. If it is too lean you need to either set the choke cap a little richer or move the pulloff to keep the blade a little more closed.
773762
 

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If your belts are squealing on acceleration, you need to tighten your belts. Attached shows where to stick the pry-bar to do so.
What carb are you running? You might need to adjust the mixture. When you get the mixture correct, then adjust the idle.
My car starts at about 1800. Might be a little fast, but at least the oil is splashing around enough to get things wet.
My normal idle is 800.
Your carb adjustments should be done at normal running temp.

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Mostly good advice that should help. All I can add is a suggestion to get the following:
  • Official Ford Shop Manual
  • Good timing light with tach and dwell
  • Good vacuum gauge
  • Good internet connection to reach out with further questions
I would lean toward a choke issue if it continues after a good cleaning. Perhaps your curb idle speed could be bumped a bit.
 
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